Centrifugally armed fuse



April 29, 1952 a. M. O'REAR 2,594,340

' CENTRIFUGALLY ARMED FUSE Filed Sept. 19, 1940 FIN" 95% ,OfHQQr Q 0 BY 2 if ATTORNEY Patented Apr. 29, 1952 UNITED STATES PATENT F Fl E.

CENTBJFUGALLY ARMED FUSE George-- M'. ORear, United States Navy Application-September 19, 1940, Serial No. 357,421

(Granted? under the: act of March 3, 1883, as

3 Claims.

This invention relatesto a fuze for use in projectiles that spin about their longitudinal axes and -more-particularly to a' fuze that is armed by the centrifugal force of its rotation.

Among the several objects of this invention are:

To provide a fuze that is safe to handle when in the unarmed condition but-is readily armcd when a projectile provided therewith is in flight;

Toprovide a fuze that is simple in construction but effective in operation; and

To provide a fuze that does not require an air driven propeller to actuate the elements thereof to change it from unarmed to armed condition.

In the drawings: V

Fig. 1 is an elevational view of a bomb pro vided with a fuze that embodies the present invention, with parts in section;

Fig. 2 is an'axial section of the fuze substantially on the line- 2--2, Fig. 3; v

Fig. 3 is a transverse section of the fuze on the line 3-3, Fig. 2; and

Fig. 4. is a fragmentary longitudinal section similar to Fig. 2 but depicting the parts of the fuze in their armed positions.

While the present invention is illustrated and described in connection with a bomb of the spinning type,-it is adapted for use in projectiles of any kind, such as those firedfrom a rifled barrel-, that spin during flight.

The bomb 5 is provided withtail vanes *6" that aregiven'an angular pitch to cause the bomb to rotate during flight as, indicated by the dot and dash line 1. Ordinarily, if the vanes 6J have a pitch of.5 the. fuze will be armed before impact but if. more-rapid arming is desired the pitch'of the vanes 6 may be increased to as much as 10, when a fall of approximately 100 it. will sufiice to efiect the arming of the fuze.

Fuze Scomprises two body members 9 and ID that are held'in assembled relation by the sheet metal member ll spun over the conical nose of member ID and over the shoulder of the member 9. In the cavity 12 formed in member 9 the detonator holder [3 is mounted to swing about pivot l4. tion l5 that covers the booster lead l6 when the parts are in unarmed condition and a detonator I! so positioned that when detonator holder l3 turns on pivot I4 the detonator I1 is brought into registration with booster lead I 6. The path followed by detonator I! when moving to the armed position is shown by broken line [8.

Spiral spring H! has one end attached to pin fixed in body member 9 and the other end The detonator holder I3 has a por-.

amended April 30; 1928; 370 O. G. 757) secured to pin 2| carried by detonator holder l3- and', as shown in Fig. 3, when the parts are in unarmedcondition the spring i9 is bent into substantially U-shape. Spring pressed detents 22 and 23 engage recesses in the detonator holder l3 to lock the detonator holder in unarmed position but when the fuze spins the centrifugalforce disengages detents 22 and 23 from detonator holder is, thus permitting spring 20 to straighten out and rotate detonator holder I3to the armed position. The position of spring l9 when the fuze is armed is indicated bydot'and dash lines l9 and the armed position of pin 2| is shown at 21'.

Mountedin body member 53 for movement along theaxis of the fuze is the firing pin 24 having an impact head 25 that extends beyond the nose of body member H3, and a collar 25 adjacent the inner end or point 2'! thereof. In the unarmed condition spring presseddetents 28 and 29 engage the inner face of collar 26 to lock the firing pin and prevent inward movement thereof but when thefuze spins the detents 28 and 29 are withdrawn by the centrifugal force and the firingpin-isfree to move inwardly. To preventfiring of detonator I? by air pressure on impact head 25 before thebomb strikes an object, the separatordisc' 35 is interposed between the point 2! of firing pin 24 and the detonator H. he disc 3! is sufliciently strong to withstand puncture due to air pressure on impact head 25 but is readily penetrated by firing pin 2d upon impact of head: 25 against an object. The shank of firing pin 24 is sufficiently rigid to puncture disc 36 and fire detonator I? when detents 28 and 29 have'been' moved out of engagement with collar 26, but if the fuze is inadvertently dropped while detents 28 and 29 are engaged with collar 26 the firing pin 24 willbend and absorb the movement of impact head 28 by deformation of the shank of the firing pin.

The invention herein described and claimed may be used and/or manufactured by or'for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim:

1. A fuze for projectiles that spin about their longitudinal axes, comprising a body, a booster charge therein, an axially extending booster lead connected to said charge, a detonator holder pivoted intermediate its ends and having a portion that covers said booster lead when said fuze is unarmed, a detonator in said holder positioned to be brought into registration with said booster lead when said holder is rotated into armed position, two spring pressed detents disposed substantially at right angles to each other and engaged with said holder to retain said holder in unarmed position but disengageable therefrom by centrifugal force, an elongated spiral spring having one end attached to said body and the other end attached to said holder to be bent into a substantially U-shape when said holder is in unarmed position and to straighten out to rotate said holder to armed position when said detents are released, a firing pin mounted to be slidable along the axis of said body and in alignment with said booster lead, said firing pin having a collar adjacent its inner end, spring pressed firing pin detents disposed diametrically opposite each other and engaged with the inner face of said collar to hold said firing pin in retracted position spaced away from the detonator holder, said diametrically disposed detents bein releasable by centrifugal force, an impact head on the outer end of said firing pin, and a separator disc disposed between the inner end of said firing pin and said detonator holder, said separator disc being constructed to hold said firing pin against movement toward said detonator under force of air pressure on said firing pin when said firing pin detent means is out of engagement with said collar, but being constructed to be penetrated by said-firing pin under impact, said firing pin being entirely spaced away from said detonator holder with said separator disc therebetween except upon penetration of said disc by said firing pin.

2. A fuze for projectiles that spin about their longitudinal axes, comprising a body, a booster charge therein, an axially extending booster lead connected to said charge, a detonator holder pivoted intermediate its ends and having a portion that covers said booster lead when said fuze is unarmed, a detonator in said holder positioned to be brought into registration with said booster lead when said holder is rotated into armed position, spring pressed detent means engaged with said holder to retain said holder in unarmed position but disengageable therefrom by centrifugal force, anelongated spiral spring having one end attached to said body and the other end attached to said holder to be bent into a substantially U-shape when said holder is in unarmed position and to straighten out to rotate said holder to armed position when said spring pressed detent means are released, a firing pin mounted in alignment with said booster lead to be slidable along the axis of said body, said firing pin having a collar adjacent its inner end, spring pressed firing pin detent means engaged with the inner face of said collar to hold said firing pin in retracted position spaced away from said detonator holder but releasable by centrifugal force.

3. A fuze for projectiles that spin about their longitudinal axes, comprising a body, a booster charge therein, an axially extending booster lead connected to said charge, a detonator holder pivoted intermediate its ends and having a portion that covers said booster lead when said fuze is unarmed, a detonator in said holder positioned to be brought into registration with said booster lead when said holder is rotated into armed position, spring pressed detent means engaged with said holder to retain said holder in unarmed position but disengageable therefrom by centrifugal force, an elongated spiral spring having one end attached to said body and the other end attached to said holder to be bent into a substantially U-shape when said holder is in unarmed position and to straighten out to rotate said holder to armed position when said spring pressed detent means are released, a firing pin mounted in alignment with said booster lead to be slidable along the axis of said body, said firing pin having a collar adjacent its inner end, spring pressed firing pin detent means engaged with the inner face of said collar to hold said firing pin in retracted position spaced away from said detonator holder but releasable by centrifugal force, a separator disc interposed between the inner end of said firing pin and said detonator holder, said separator disc being constructed to hold said firing pin against movement toward said detonator under force of air pressure on said firing pin when said firing pin detent means is out of engagement with said firing pin collar but being constructed to be penetrated by said firing pin under impact, said firing pin being suificiently rigid to puncture said disc upon impact on said firing pin when said firing pin detent means is out of engagement with said collar, and said firing pin being constructed to bend and absorb movement of its impact head by deformation of the shank of the firing pin under accidental impact when said firing pin detent means is engaged with the inner face of said collar.

GEORGE M. ORE'AR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

